The influential pair had criticised each other publicly following a disagreement at the end of Euro 2008, prompting Germany legend Franz Beckenbauer to liken them to "two children in Kindergarten".

However, their working relationship has been restored after a "constructive" phone call, according to Bierhoff.

"It was an open and constructive discussion in which we both reflected on what has happened in recent weeks," said Bierhoff.

Ballack, who missed Germany's last two games due to injury, added that "everything was discussed and the foundations for a professional cooperation have been laid".

The Chelsea midfielder was seen to insult Bierhoff at the end of the Euro 2008 final when the former Germany striker requested he hold up a banner with the rest of the team to thank the fans for their support.

Recent clear-the-air talks apparently brought no end to their feud as both used the media to openly criticise each other and question their importance to the national team.

Germany coach Joachim Low is glad the issue has finally been dealt with.

"I am delighted that this has been cleared up with an open dialogue with each other," he said.

"We can now look forward to our upcoming World Cup qualifiers at home to Russia and Wales with the highest level of concentration."

Ballack is expected to be fit for those games in early October as he returned to training for Chelsea recently.